Rigid expanded polyurethane foam (REPF)

This product is available in both sheet form (to order) or liquid (2 part), unlike polystyrene REPF can be used in contact with polyester resin and is often employed as an insulation material from heat or cold and also filling cavities for buoyancy and water ingress prevention.
The liquid form is available in two densities High & low, the high density foam is used as a cavity filler where great strength is required also used to cast blocks for carving, sanding and machining when making mould masters/plugs etc, main uses include automotive body parts wings, sills, bumpers, aerofoils, skirts etc. Both densities can be used for casting in moulds and when its expanding in a confined space forms a skin and produces a smooth shiny surface.

Low density foam is used mainly for filling buoyancy chambers in boats but also produces a very effective insulation barrier, expanding in ideal conditions to approx 20-24 times its original volume.
Prices HERE
Spec and mixing guide sheets are available here HIGH density LOW density.